[MC][Mips] Rename MipsMCAsmInfo to MipsELFMCAsmInfo

[hpoussin]

Also change MipsAsmPrinter::emitStartOfAsmFile to emit ELF-related sections only when using ELF output file format.

[hpoussin]

This is an extract of PR #107744
This commit is better viewed when ignoring whitespace changes.

[brad0]

cc @yingopq

[hpoussin]

Ping.
This commit is required to add (in a later PR) the class MipsCOFFMCAsmInfo.

[wzssyqa]

There is a failure on Windows. Can you have a look at it?
LLVM :: CodeGen/Mips/no-odd-spreg.ll

[hpoussin]

There is a failure on Windows. Can you have a look at it? LLVM :: CodeGen/Mips/no-odd-spreg.ll

Fixed. It seems Windows hosts default to COFF output while Linux hosts default to ELF.
However, this test assumed ELF output without requesting it, and this PR starts to react on chosen output format.

[llvm-ci]

LLVM Buildbot has detected a new failure on builder premerge-monolithic-linux running on premerge-linux-1 while building llvm at step 7 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/153/builds/13380

Here is the relevant piece of the build log for the reference

Step 7 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'ORC-x86_64-linux :: TestCases/Linux/x86-64/priority-static-initializer.S' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 4: /build/buildbot/premerge-monolithic-linux/build/./bin/clang   -m64  -c -o /build/buildbot/premerge-monolithic-linux/build/runtimes/runtimes-bins/compiler-rt/test/orc/X86_64LinuxConfig/TestCases/Linux/x86-64/Output/priority-static-initializer.S.tmp /build/buildbot/premerge-monolithic-linux/llvm-project/compiler-rt/test/orc/TestCases/Linux/x86-64/priority-static-initializer.S
+ /build/buildbot/premerge-monolithic-linux/build/./bin/clang -m64 -c -o /build/buildbot/premerge-monolithic-linux/build/runtimes/runtimes-bins/compiler-rt/test/orc/X86_64LinuxConfig/TestCases/Linux/x86-64/Output/priority-static-initializer.S.tmp /build/buildbot/premerge-monolithic-linux/llvm-project/compiler-rt/test/orc/TestCases/Linux/x86-64/priority-static-initializer.S
RUN: at line 5: /build/buildbot/premerge-monolithic-linux/build/./bin/llvm-jitlink -orc-runtime=/build/buildbot/premerge-monolithic-linux/build/./lib/../lib/clang/20/lib/x86_64-unknown-linux-gnu/liborc_rt.a /build/buildbot/premerge-monolithic-linux/build/runtimes/runtimes-bins/compiler-rt/test/orc/X86_64LinuxConfig/TestCases/Linux/x86-64/Output/priority-static-initializer.S.tmp | FileCheck /build/buildbot/premerge-monolithic-linux/llvm-project/compiler-rt/test/orc/TestCases/Linux/x86-64/priority-static-initializer.S
+ FileCheck /build/buildbot/premerge-monolithic-linux/llvm-project/compiler-rt/test/orc/TestCases/Linux/x86-64/priority-static-initializer.S
+ /build/buildbot/premerge-monolithic-linux/build/./bin/llvm-jitlink -orc-runtime=/build/buildbot/premerge-monolithic-linux/build/./lib/../lib/clang/20/lib/x86_64-unknown-linux-gnu/liborc_rt.a /build/buildbot/premerge-monolithic-linux/build/runtimes/runtimes-bins/compiler-rt/test/orc/X86_64LinuxConfig/TestCases/Linux/x86-64/Output/priority-static-initializer.S.tmp
/build/buildbot/premerge-monolithic-linux/llvm-project/compiler-rt/test/orc/TestCases/Linux/x86-64/priority-static-initializer.S:8:16: error: CHECK-NEXT: expected string not found in input
// CHECK-NEXT: constructor 200
               ^
<stdin>:3:16: note: scanning from here
constructor 100
               ^
<stdin>:5:1: note: possible intended match here
destructor
^

Input file: <stdin>
Check file: /build/buildbot/premerge-monolithic-linux/llvm-project/compiler-rt/test/orc/TestCases/Linux/x86-64/priority-static-initializer.S

-dump-input=help explains the following input dump.

Input was:
<<<<<<
          1: constructor 65535 
          2: constructor 200 
          3: constructor 100 
next:8'0                    X error: no match found
          4: main 
next:8'0     ~~~~~
          5: destructor 
next:8'0     ~~~~~~~~~~~
next:8'1     ?           possible intended match
>>>>>>

--

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